Masks leave parts showing

[bbwd]

Whenever I create a mask I end up with parts of the area I wanted to mask showing. I then have to remove them with the paint brush.

I have to blur backgrounds on photos so that the person is more prominent or to 'remove' people in the background. I usually use the selection brush tool along with the freehand selection tool to create a selection, then click 'refine' and, if needed, brush over the edges where the selection could be better - usually around the head and hair where the refine process works as expected.

It's usually on hard edged shapes where the problem occurs - when the person is wearing a hat, or around their clothing. After selecting and clicking 'refine', I very rarely adjust any settings in the refine dialogue box, it's left as it appears. What I am left with is shown in the photo sample below.

Can anyone help me with a solution to this issue to get it right first time without having to use the paint brush?

 

FYI: MacOS 10.15.17 on a 27" iMac but this problem also happens on a MBP running the same OS.

[NotMyFault]

Hi,

 

this is a commonly known shortcoming of the „refine“ tool. Don’t use it for hard edges.

Unfortunately for portrait images, you have both e.g. the hair part where you need it, and the rest of the body where you don’t want to refine.

One method is the following process:

• create the selection without refining
• Use rectangular selection in „intersect“ mode and remove area with hair where you want to apply refine
• create mask from selection
• create selection of hair again (or use spare channel, or stored selection)
• Use rectangular selection in intersect mode to select hair only
• refine
• add refined area to mask (several ways to dorthin via channels panel)

Unfortunately Affinity makes it very complicated, as there is no easy way to use masks in an additive way. Several users postet tutorials with workarounds, e.g. by using double / triple negation (invert filter). 

 

[NotMyFault]

In the Case of masking a hat, i would suggest to not use refine at all.

Instead, use a brush of the masking category, and paint over the edge area to give a diffusion effect. Where needed.

[NotMyFault]

Another tip:

• convert to RGB/16. I often get better selection results.
• use channels panel and check which color channel gives the best contrast for the critical region. Leave only this channel activate during selection and refine.
• sometimes I copy the image and use heavy adjustment or tone map persona to boost local contrast to maximum. Use this layer for selection, then hide or remove.